text: Diamonds cubic structure is in the Fdm space group (space group 227), which follows the face-centered cubic Bravais lattice. The lattice describes the repeat pattern; for diamond cubic crystals this lattice is "decorated" with a motif of two tetrahedrally bonded atoms in each primitive cell, separated by  of the width of the unit cell in each dimension. The diamond lattice can be viewed as a pair of intersecting face-centered cubic lattices, with each separated by  of the width of the unit cell in each dimension. Many compound semiconductors such as gallium arsenide, β-silicon carbide, and indium antimonide adopt the analogous zincblende structure, where each atom has nearest neighbors of an unlike element. Zincblendes space group is F3m, but many of its structural properties are quite similar to the diamond structure.
  The atomic packing factor of the diamond cubic structure (the proportion of space that would be filled by spheres that are centered on the vertices of the structure and are as large as possible without overlapping) is  significantly smaller (indicating a less dense structure) than the packing factors for the face-centered and body-centered cubic lattices. Zincblende structures have higher packing factors than 0.34 depending on the relative sizes of their two component atoms.
  The first-, second-, third-, fourth-, and fifth-nearest-neighbor distances in units of the cubic lattice constant are  respectively.